Safety device for elevators.



O. I. NIGH.

SAFETY DEVICE FOR'ELEVATORS.

APPLICATION FILED FEB.1I. 915. 1210 351. Patented Dec. 26,1916.

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O. I. NIGH.

SAFETY DEVICE FOR ELEVATORS.

APPLICATION HLED FEB. 11, 1915- w 6 in LQififii' 1, Rammed Dec. 26,1910.

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OMAR I. HIGH, 0]? WASHINGTON, DISTRICT OF COLUMBIA.

SAFETY DEVICE FOR ELEVATORS.

Application filed February 11, 1915.

To all whom it may concern:

Be it known that I, OMAR I. NIGH, a citizen of the United States, residing at Tashington, in the District of Columbia, have invented new and useful Improvements in Safety Devices for Elevators, of which the following is a specification.

My invention relates to elevators, and more particularly to safety devices for the same, and has as an object to provide a safety device which must be manually oper ated and manually maintained in a predetermined position to render the car capable of movement, but which is locked against such actuation until certain predetermined conditions are complied with.

It is an object of this invention to lock the safety device against actuation, and thereby prevent the movement of the car, until the shaft door of the floor at which the car is standing is entirely closed, whereby any premature movement of the car before the door is closed is prevented; thus preventing persons, while the car is in motion, from attempting to pass into or out of an ascending or descending car through a partially closed door.

It is a further object of this invention to locate a safety device which normally renders the car inoperative, but which cannot be actuated until the door is closed, in such position that it must be operated from one side of the door-way of the elevator, the controlling mechanism being positioned at the opposite side of the doorway, whereby the operator must stand in correct position before the door-way with one arm extended to the operating handle of the safety device and the other arm to the controlling mechanism; thus, preventing persons from standing or moving onto or across the threshold of the door-way while the car is about to be put into or is in motion; removing the necessity of a gate; and compelling the operator to give his undivided attention to the operation of the car.

Furthermore, my construction insures that all the doors of the well or shaft are closed, as the operator cannot leave any particular floor at which the car may be standing until the shaft door at that floor is closed; thus obviating the danger of persons passing through an open door-way of the shaft after the car has moved away from the same and sustaining injury from the resulting fall Specification of Letters Patent.

Patented Dec. 26, 1916.

Serial No. 7,524.

down the shaft; and, thus also obviating the necessity ofproviding each door with a separate safety device.

lthe above and other objects of the invention may be accomplished with the structure hereinafter described in detail, reference being had to the accompanying drawings forming a part of this specification wherein like reference numerals denote corresponding parts in the several views, and in which Figure 1 is a vertical cross-section taken on line 11 of Fig. 2, of an elevator shaft and car disclosing one embodiment of my invention as applied to an electrically-controlled elevator. Fig. 2 is a horizontal cross-section of the elevator shaft and car shown in Fig. 1. Fig. 3 is an enlarged detail view of the cutout switch which normally renders the controlling mechanism dead or inactive. Fig. 4 is a vertical crosssection of an elevator shaft andcar showing one embodiment of my invention as applied to a mechanically-controlled elevator. Fig. 5 is a horizontal cross-section of the elevator shaft and car shown in Fig. 4. Fig. 6 is an enlarged detail view of the cam shoes of the gripping mechanism, which render the car normally inoperative, with parts of the shoes broken away. Fig. 7 is a sectional view of the gripping mechanism showing a shoe in position against the cable. Fig. 8 is an enlarged detail vertical elevation of the door engaging shoe.

Referring to Figs. 1, 2 and 3, which disclose one embodiment of my invention as applied to an electrically-controlled elevator, 1O designates the shaft provided with the usual guideways 11, and 12 designates the car working within the shaft provided upon the under side of its bottom with guide members 13 which engage the guideways 11. On one side of the door-way of the elevator car is positioned an electric controller 14 which may be of any suitable design, the same here being conventionally shown, as it comprises no part of this invention. The car of the elevator is shown as standing at one of the floor landings of a building with the door 15 of the elevator shaft or well in closed position, the door 15 being mounted for slidable movement in the track 16. On the inside of the door 15 adjacent the upper end thereof is provided a strip or shoe 17 which is adapted to prevent the actuation of the safety device when the shaft door is open, as will hereinafter be explained. The safety device comprises a normally out of contact cut-out switch which is in series with the controlling mechanism, and means for manually throwing and maintaining the switch mechanism in contact position when it is desired to set and maintain the car in motion. The switch mechanism, designated by the numeral 18, is, in the present disclosure, arranged upon the underside of the bottom of the car. This switch mechanism may be of any suitable design or construction, but, in the present instance, is disclosed as comprising a block of any suitable non-conducting material, having a cavity or cut-out portion 20 in which is located a fixed bar 21 also of non-conducting material. EX- tending through the block and the bar 21 are fixed contact posts or terminals 22, and 23, against the ends of which is adapted to seat a contact plate 24 mounted on the stem 25, which stem extends into an aperture in the bar 21. A spiral spring 26, encircling the stem 25 and having one end seated against the bar 21 and the other end against a plate 27 rigidly secured to the stem, normally holds the contact plate 24. from contact with the terminals 22 and 23. The controller 14 and the switch mechanism 18 are connected in series by means of a cable 28 which passes through the pipe 28 to the controller, back through the pipe to one of the terminals 22 or 23, and from the other terminal to the operating or hoisting mechanism. The operating mechanism may be of any type as my invention is applicable to water, steam, or electrically operated elevators. The means for throwing the switch into contact position comprises a vertical rock-shaft 29 extending. from the top of the car to and through the floor of the same at the side of the doorway opposite to the position of the controller, the end of the shaft which protrudes below the floor being provided with an arm 30. The shaft 29 is provided with asuitable operating handle 31 which is pivotally connected thereto, so that the handle may be lowered when not in use. The arm 30, when the shaft 29 is rocked in the correct position, engages the end of the stem 25 of the switch and forces the contact plate 2 1 into contact with the terminals 22 and 23, and the circuit, including the switch mechanisn1 18 and the controller 1 1, is closed, and the elevator car can then be operated or set in motion. The cont-act plate 2 1 is normally withdrawn or held out of contact with the terminals 22 and 24L of the switch by means of the spring 26, so that to place the car in motion and to retain the same in motion, it is necessary that the handle 31 be operated to turn the shaft 29 to close the switch 18 and be manually maintained in such position. Extending radially from the rock shaft 29 near the upper end of the same, and lying in the horizontal plane of the shoe or strip 17 of the door 15, is an arm 32 having secured to its end a vertical shoe 33. This arm 32 may be constructed for longitudinal adjustment and is out of radial alinement with the arm 30, and is adapted to extend through the front wall of the car and protrude outwardly into the space between the wall of the shaft 10 and the car 12, the arm being of such length that it cannot contact with the wall of the shaft when the arm is turned into its outermost position. The arm 32 is so arranged, however, that when the rock-shaft 29 is turned to throw the switch into contact, the arm and the shoe 33 justclear the inner end of the shoe or strip 17 when the door is fully closed. i Vhen the door is open, although it may be but to a slight extent, the shoe 33, when the rock shaft is attempted to be operated, engages the inner face of the shoe or strip 17 and thereby prevents the rocking of the shaft, and thus the switch mechanism cannot be thrown into contact. The shoe or strip 17 thus serves as a lock and prevents the actuation of the safety device and the operation of the car while the door is open. The arm 32 extends, when in its outermost position, at an angle to the wall of the shaft, and the ends of the shoe 33 are turned inwardly so that should one of the shaft doors be open, and the shoe 33, when the car is in movement, strike the strip 17, the rock shaft 29 would be rotated in a direction to throw the switch out of contact and stop the car and thereby prevent injury to the safety device.

Referring now to Figs. 4:, 5, 6 and 7 of the drawings wherein is disclosed a mechanically controlled elevator, the car 12 is shown as standing at a floor landing of a building, the door 15 of the shaft being in closed position and provided with a shoe or strip 17. The means for mechanically controlling the elevator may be of any approved form, but is here shown, for purposes of illustration, as comprising an op erating lever 34: located at one side of the door-way of the car and extendingthrough the floor of the latter, the lower end of the lever being provided with a horizontal crossbar 35 which is fixed at its intermediate portion thereto. Attachedto guides at the ends of the cross-bar 35 are cables 36 which pass about pulleys 37 secured diametrically at opposite points to the face of the pulley 38 which is arranged in the bottom of the shaft. Passing about the pulley 38 is a cable 39 which, should the elevator be hydraulically operated, passes around a sheave (not shown) which operates the hydraulic valve, or, should the elevator be electrically operated, the cable passes to the switch mechanism which controls the electrical-operating means. When the lever 34 is thrown to either side,the direction in which it is moved depending on whether it is desired to cause the car to ascend or descend one arm of the cross-bar 35 is elevated and the other is lowered, and by means of cables 36 a partial rotation of the pulley 38 is effected, the movement of the pulley 38 being transmitted to the elevator operating or hoisting mechanism by cable 39. The safety device comprises a gripping mechanism. 40, and means for operating it. The gripping mechanism which is preferably arranged upon the bottom of the car, as shown in Fig. 4, comprises a hollow shell or casing 41 having a preferably rounded outer wall 42 projecting beyond the side of the car and providing a passage for a vertical cable 43 in the shaft, and a pair of vertically spaced apart clutch shoes 44 of cam shape and having concave gripping faces conforming to the contour of the cable and adapted to bind, at times, thereagainst. The cam shoes 44 are pivoted near one end in the casing 41, the free ends diverging toward the cable The inner ends of the shoes 44 overlap and are connected by a pin 45, passing through the elongated slots 46, to a rod 47 adapted to swing the cam shoes into and out of engagement with the cable 43. By this engagement with the cable it will be seen, that when the rod 47 throws the free ends of the cam shoes 44 against the cable 43, upon the upward movement of the car, the upper shoe wedges the cable against the outer wall 42 of the casing 41, and upon the downward movement of the car the lower shoe wedges the cable 43 against the wall 42. The means for actuating the gripping mechanism comprises a rock shaft 48 located at the side of the door opposite that of the controlling lever 34 and extending from the top of the car to and through the floor of the same, the lower protruding end being provided with an outwardly projecting arm 49, which arm is connected to one end of the lever 50 mounted on a stub shaft 51. The other end of the lever 50 is connected to the clutch shoes 44 by means of the connecting rod 47. A spring 52 is attached to the arm 49 to normally hold the lever 50 in such position that the clutching shoes 44 normally grip the ca ble 43. When the shaft 48 is manually rocked to overcome the tension of spring 52, a suitable handle 53 being provided on the shaft for this purpose, the rod 47 is moved toward the gripping mechanism and the free ends of the cam shoes 44 are withdrawn from engagement with the cable 43, whereby the cable is released to permit the manip ulation of the controlling mechanism. The means for connecting the gripping mechanism to the controlling mechanism is located in one of the rear angles of the shaft and comprises the cable 43 passing'over a pulley 54 at the top of the shaft and about a pulley 55 located in the bottom of the shaft. .A cable 56 passes about the pulley 38 and pulley 55. When the cable 43 held against movement by means of the gripping mechanism above-explained, the pulleys 38 and 55 due to the gripping action of the ca bles 43 and 56, cannot rotate and thereby any movement of the lever 34 is prevented, and the car is rendered inoperative. For the purpose of preventing the actuation of rocking of the shaft 48 when the door is open, the shaft is provided with an arm 57 having a shoe 58 which is on a horizontal level with the shoe 17 on the door 15 and which is adapted to just clear the inner end of the shoe 17 when the door is closed. /Vhen, however, the door is open the shoe 58 engages the inner face of the door shoe 17 and locks the shaft against rocking movement to thereby prevent the operation of the controlling mechanism when the door is open.

It will be noted from the above description that when it is desired to set a car, which is provided with my device, into motion the following prerequisites must be complied with: The operator must first close the door and make sure that it is fully closed; take his position before the doorway; extend one hand to the controlling mechanism and the other to the safety device; and actuate the safety device and the controlling mechanism while he is in said position, the actuation of said safety device being prevented should the door be open or partially open.

The means for operating the elevator car, that is the hoisting mechanism is not disclosed in the present drawing, as such does not form any part of my invention, but it is understood that either embodiment of my device is applicable to any form of elevator whether it be steam, water or electrically operated.

It is to be understood that although the shaft door in the present disclosure prevents the actuation of the safety device when the door is open, the inside or car door, where such is provided, may be used to prevent such actuation of the safety device, and various other changes and modifications may be made within the spirit of the invention and without departing from the scope of the following claims.

I claim 1. In an elevator, the combination with a car, and a door, of normally inoperative power controlling mechanism for operating said car located at one side of the doorway thereof, a safety device on the opposite side of said doorway adapted to be manually operated and maintained for rendering said car operative whereby the operator is compelled to stand in said doorway to manipulate said car, and means rendering said safety device operative while the door is open.

2. In an elevator, the combination with a car, and a door, of normally inactive power controlling mechanism for operating said car at one side of the doorway thereof, a safety device on the opposite side of said doorway which must be manually operated and manually maintained in a predetermined position to render and continue active said power controlling mechanism, and means adapted to be engaged by said door when the latter is open whereby to prevent manipulation of said safety device while the door is open.

3. In an elevator, the combination with a car, and a door, of normally inactive power controlling mechanism for operating said car located at one side of the doorway thereof, a safety device on the opposite side of said doorway adapted to be manually operated and maintained to render active said power controlling mechanism, means to maintain said safety device normallyin an inactive position, and means for locking said safety device against actuation while the door is open.

4. In an elevator, the combination with a shaft, a shaft door and a car, of a mechanical controlling mechanism for operating said car, a gripping mechanism normally rendering said controlling mechanism inoperative, operating means for said gripping mechanism which must be manually operated and manually maintained in a predetermined position for releasing said gripping mechanism to render and continue said controlling mechanism capable of operation,

said operating means for said gripping mechanism being located on the side of the elevator door opposite to the controlling mechanism, whereby the operator is compelled to stand in the doorway to manipulate the car, and means on said operating means for preventing the operation of the latter when the door is open,

5. In an elevator, the combination with a shaft, a shaft door and a car, of a mechanical controlling mechanism for operating said car located on one side of the doorway of the car, a gripping mechanism normally rendering said controlling mechanism inoperative, a rock shaft on the opposite side of said doorway connected to said gripping mechanism and which must be manually rocked and manually maintained in a predetermined position to release said gripping mechanism to render and continue said controlling mechanism capable of operation, and means on said rock shaft adapted to engage the door when the latter is open to prevent the operation of said rock shaft when the door is open.

In testimony whereof I have hereunto set my hand in presence of two subscribing witnesses.

OMAR I. NIGI-I.

lVitnesses:

GERTRUDE M. STUOKER, T. CLAY LINDSEY.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. G. 

